BMI Calculator

Body mass index (BMI) compares your weight with your height. It is a quick first check of whether your weight is in a healthy range for adults.

Weight

Height

Use the Asian BMI rangesWHO suggests lower cut-offs for people of Asian origin, where health risks start at a lower BMI.

Enter your details to see your result.

These numbers are estimates for healthy adults, not medical advice. If you have a health condition, are pregnant or are under 18, speak to a doctor first.

How it works

BMI is your weight in kilograms divided by your height in metres squared. In US units, it is 703 times your weight in pounds, divided by your height in inches squared.

For most adults, the World Health Organization groups the results like this: under 18.5 is underweight, 18.5 to 24.9 is a healthy weight, 25 to 29.9 is overweight and 30 or more is obese. For people of Asian origin, overweight starts at 23 and obese at 27.5.

BMI doesn't know the difference between fat and muscle. A muscular lifter can have a high BMI and very little fat, so use it together with your waist size and how you look and feel.

Questions

What is a healthy BMI?

For most adults, a BMI from 18.5 to 24.9 is considered healthy. For people of Asian origin, WHO suggests 18.5 to 22.9.

Is BMI accurate for people who lift weights?

Not always. Muscle weighs a lot, so strong, muscular people can show as overweight while having little body fat. Waist size is a useful second check.

Does BMI work for children?

No. Children and teenagers use BMI-for-age charts, because their bodies are still growing. This calculator is for adults.

How can I lower my BMI?

Eat a little less than you burn, eat enough protein, lift weights and stay active every day. Our guide to losing belly fat explains the plan.

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